SALEM, Ore. - As Congress debates the first national immigration overhaul in decades, a state-level push advancing rights for people in the U.S. illegally has picked up momentum across the country.

Among the patchwork changes to state law taking effect from Maryland to Oregon are provisions that lower tuition rates, advance employment opportunities and repeal hard-line regulations approved within the last decade.

Crowds at May Day rallies across the nation cheered the developments and urged federal progress. Legislative action in several states, meanwhile, coincided with speeches and marches.

"I have a message for Congress and the president," said Jeff Stone, representing Oregon's nursery industry at a rally of about 2,000 in Salem. "Stop talking, and start acting."

Stone spoke shortly after Oregon's Democratic governor, John Kitzhaber, signed a bill allowing immigrants to drive legally in the state.

Many such state-level proposals go beyond what is being discussed on Capitol Hill, and the significant, if piecemeal, shift shows lawmakers reacting to a pendulum swing in public opinion that helped usher many of them into office. But experts also say state legislators have been spurred by halting progress in Washington, D.C.

"The vacuum created by inactivity at the federal level is certainly a major factor, if not the major factor, in states' action on this issue," said Muzaffar Chishti, director of the New York division of the nonpartisan Migration Policy Institute.

At least 15 states are in various stages of considering bills that would further integrate immigrants, and several others already have passed such legislation this year. This group is larger than the handful of states moving the other direction, though there are exceptions.

Matt Mayer, a visiting fellow at the conservative Heritage Foundation, said he doesn't think this year has been significantly different at the state-level than previous years because such immigration proposals have been around for more than a decade.

"It's just states trying to deal with what they perceive to be the problem," he said.

Georgia lawmakers, for example, expanded a law passed in 2011 to crack down on illegal immigration. And Arizona and Nebraska officials have refused to grant driver's licenses to young immigrants authorized to be in the country under the federal Deferred Action for Childhood Arrivals directive.

But this is mild compared with the climate of recent years where anti-illegal immigration attitudes dominated the national debate.

"This is an interesting evolution," Chishti said.

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